Sky email worked on my phone yesterday but won't receive emails today. It will however send emails

[Jamboat]

Can't receive emails through Gmail but I can send emails 

[caesarome]

What is happening when you go to your Gmail account to receive emails from your Sky account ?

[Jamboat]

When I open Gmail there are no new emails. If I sign in to sky mail then I can read my new email 

[caesarome]

Login in here:

https://mail.google.com/mail/

If you go to Settings > See all settings > Accounts & Import.

It should show you when it last checked your Sky email account so what is shown here, you can also get it to check the account.